06673291d7
When a peer sends a dictionary entry update with a value (the else
branch at line 2109), the entry id decoded from the wire was never
validated against dc->max_entries before being used as an array index
into dc->rx[].
A malicious peer can send id=N where N > 128 (PEER_STKT_CACHE_MAX_ENTRIES)
to:
- dc->rx[id-1].de at line 2123: OOB read followed by atomic decrement
and potential free of an attacker-controlled pointer via
dict_entry_unref()
- dc->rx[id-1].de = de at line 2124: OOB write of a heap pointer at
an attacker-controlled offset (16-byte stride, ~64 GiB range)
The bounds check was added to the key-only branch in commit f9e51beec
("BUG/MINOR: peers: Do not ignore a protocol error for dictionary
entries.") but was never added to the with-value branch. The bug has
been present since dictionary support was introduced in commit
8d78fa7def5c ("MINOR: peers: Make peers protocol support new
"server_name" data type.").
Reachable from any TCP client that knows the configured peer name
(no cryptographic authentication on the peers protocol). Requires a
stick-table with "store server_key" in the configuration.
Fix by hoisting the bounds check above the branch so it covers both
paths.
Must be backported as far as 2.6.
HAProxy
HAProxy is a free, very fast and reliable reverse-proxy offering high availability, load balancing, and proxying for TCP and HTTP-based applications.
Installation
The INSTALL file describes how to build HAProxy. A list of packages is also available on the wiki.
Getting help
The discourse and the mailing-list are available for questions or configuration assistance. You can also use the slack or IRC channel. Please don't use the issue tracker for these.
The issue tracker is only for bug reports or feature requests.
Documentation
The HAProxy documentation has been split into a number of different files for ease of use. It is available in text format as well as HTML. The wiki is also meant to replace the old architecture guide.
Please refer to the following files depending on what you're looking for:
- INSTALL for instructions on how to build and install HAProxy
- BRANCHES to understand the project's life cycle and what version to use
- LICENSE for the project's license
- CONTRIBUTING for the process to follow to submit contributions
The more detailed documentation is located into the doc/ directory:
- doc/intro.txt for a quick introduction on HAProxy
- doc/configuration.txt for the configuration's reference manual
- doc/lua.txt for the Lua's reference manual
- doc/SPOE.txt for how to use the SPOE engine
- doc/network-namespaces.txt for how to use network namespaces under Linux
- doc/management.txt for the management guide
- doc/regression-testing.txt for how to use the regression testing suite
- doc/peers.txt for the peers protocol reference
- doc/coding-style.txt for how to adopt HAProxy's coding style
- doc/internals for developer-specific documentation (not all up to date)
License
HAProxy is licensed under GPL 2 or any later version, the headers under LGPL 2.1. See the LICENSE file for a more detailed explanation.